This invention relates generally to a method and apparatus for monitoring the tension of a track on an earthworking machine and, more particularly, to a method and apparatus for determining the tension on the slack-side of a track on an earthworking machine.
Earthworking machines which use track-type propulsion, e.g., track-type tractors, tracked agricultural machines, track-type loaders, excavators, and the like, are frequently used in earthworking applications due to the inherent advantages obtained from the use of tracks as compared to comparable wheeled machines. For example, tracked machines offer greater traction and improved flotation in wet or loose soils and sands.
The tracks on a tracked machine are subjected to heavy loading in typical earthworking operations. In particular, larger tracked machines, by nature of their increased power capabilities and increased demands on their performance, are prone to place great load demands on the tracks. Historically, the high load demands have been compensated for by increasing the strength and durability of the track components. However, these increases are also accompanied by increased costs. In addition, the increases in strength of the track components are limited by practical considerations, such as physical constraints.
One of the more significant sources of stress in the tracks of the tracked machine is caused by improper tension in the slack catenary portions of the track, i.e., those portions of the track which are designed to exhibit some slack as a function of the direction of travel of the earthworking machine. For example, undue stress on the track may be caused by too much tension in the slack catenary portions. Therefore, it is desired to have the capability to monitor the tension in the catenary portions of the track for the purpose of controlling the slack-side tension and reducing the stress being placed on the tracks of a track-type earthworking machine.
The present invention is directed to overcoming one or more of the problems as set forth above.
In one aspect of the present invention a method for determining a tension of a track on an earthworking machine, the track having a front catenary portion and a rear catenary portion, is disclosed. The method includes the steps of determining a direction of motion of the earthworking machine, determining a value of tension of the front catenary portion in response to determining the direction of motion of the earthworking machine to be in a forward direction, and determining a value of tension of the rear catenary portion in response to determining the direction of motion of the earthworking machine to be in a reverse direction. In another aspect of the present invention an apparatus for determining a tension of a portion of a track on an earthworking machine, the track having a front catenary portion and a rear catenary portion, is disclosed. The apparatus includes means for determining a direction of motion of the earthworking machine, and a controller located on the earthworking machine, the controller being adapted to determine a value of tension of the front catenary portion in response to determining the direction of motion of the earthworking machine to be in a forward direction, and determine a value of tension of the rear catenary portion in response to determining the direction of motion of the earthworking machine to be in a reverse direction.